When Charlie Parker died in 1955, graffiti artists scrawled the words "Bird Lives!" on New York's walls. Parker had been the most gifted creator of bebop, the jazz soundtrack to 1940s existentialism and hipster bohemianism. The Kansas City alto saxophonist's impassioned attack, bluesy tone, and dazzling melodic inventiveness seemed like the quintessential celebration of the intense but fleeting moment.

Charlie Parker was born in Kansas City on 29 August, 1920. His father, who left home when Parker was 11, was a vaudeville performer. His mother Addie doted on her son, and bought him his first saxophone. When Charlie was 14, and Addie was out all night working as a cleaner, he took the opportunity to hang around the Kansas jazz clubs, where he heard the leading saxophonists of the 30s, including the great Lester Young.

Fascinated by Young's melodic conception and narrative strengths, the teenage Parker taught himself to play alto sax. He didn't realise that most jazz music was only played in a few favourite keys, so he learned them all - an accidental skill that later became a trademark feature of his improvising, namely the ability to move away from a tune's "home" key and back without losing the thread. But the progress toward a jazz revolution wasn't without its pitfalls. Sitting in with swing legends including Count Basie's drummer Jo Jones one night at Kansas City's Reno Club, Parker lost his place attempting such a risky modulation on a fast I Got Rhythm. Jones gonged him off by unscrewing a cymbal and tossing it at the humiliated teenager's feet.

But by 1939, when Charlie Parker joined the big-time swing band of pianist Jay McShann, he was overcoming new technical hurdles by the day. He began stacking swing's relatively simple chords with extra notes on top, using these, instead of the usual constituent notes, as the basis for fresh improvisations. "I came alive," Parker said, when he cracked this problem while dissecting the structure of the swing tune Cherokee.

But bebop wasn't born simply out of Parker's genius. It was waiting to happen, bubbling up out of the boredom of the younger musicians playing commercial swing, a desire among many African-Americans to increase respect for jazz as art-music amid the pressures and disruptions of the second world war. In New York, Charlie Parker soon met kindred spirits such as drummer Kenny Clarke, pianist Thelonious Monk, guitarist Charlie Christian and trumpeter Dizzy Gillespie. Late at night, after the swing shows they played for a living, the young experimenters would get together at Minton's Playhouse in Harlem and other after-hours haunts. In 1944, Parker began recording under his own name. By the following year, he was in his astonishing prime, beginning to produce the sessions that would come to be seen as landmarks in jazz history, as significant as Louis Armstrong's Hot Fives and Sevens two decades earlier.

Here's Parker in 1946 on Dial Records's account of his classic bop composition Cherokee. An unsteady-sounding 19 year-old Miles Davis is on trumpet and Dodo Marmarosa is on piano. It's fascinating to compare the construction of Charlie Parker's alto sax improvisation - he's the first sax soloist - with a still swing-sounding Lucky Thompson on tenor. Jazz is on the cusp, about to be transformed forever.